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Chapter 31: Q. 9 (page 900)

Older televisions used a loop antenna like the one in FIGUREQ31.9.How does this antenna Work?

Short Answer

Expert verified

An electromagnetic wave passes through a loop antenna, the current produced by magnetic induction in Faraday's law is used.

Step by step solution

01

Figure for old television with loop antenna

Figure of an ancient television with a loop antenna,

02

Explanation

When an RF current carrying coil is turned into a loop, it can be used as an antenna, known as a loop antenna.

The currents that pass through this loop antenna will be phased.

The magnetic field will be perpendicular to the whole current-carrying loop.

Application:

Electrically tiny loop and coil antennas have traditionally been used as antennas in medium- and long-wave broadcast radio receivers.

A single-turn loop antenna is frequently used to receive UHF channels. Because "rabbit ears" antennas only cover the VHF bands.

They are sometimes used in conjunction with a UHF loop put on the same base to cover all TV channels.

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a. What are E→and B→at a point on the loop as measured by a scientist in the laboratory? Include both strength and direction.

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e. Show that your fields of parts b and d are the same.
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